Epistemology naturalized: Quine's intervention in the debate concerning the problem of knowledge

The present paper attempts critical navigation of what could be referred to as the Quinean Intervention in the debate concerning knowledge. This problem easily represents the central concern of traditional epistemology, particularly since the modern period. Its retrospective statement finds expression in the ancient definition of knowledge as justified true belief (JTB). Among the problems easily identified with the traditional conception of knowledge is exhaustive or conclusive justification, which is to form the base of the structure of knowledge. Philosophers across the spectrum of discourse have risen to respond to the problem. Prominent among the position is foundationalism and coherentism as theories of justification. However, these theoretical representations are never able to proffer the conclusive justification condition; thus, epistemology's traditional problem has mainly remained unresolved. Philosophers across the board have therefore proffered several alternatives. One of such is the project to naturalize epistemology – a program famously identified with W.V.O. Quine. The paper examines Quine's position to move epistemology from philosophy to psychology. This project, the paper argues, stripped epistemology of its normative status. Therefore, it cannot be regarded as a philosophical proposal, as philosophy is essentially prescriptive, not descriptive, matters of ought not matters of is or matters of values not matters of fact. For this reason, the paper rejects the Quinean project, describing it as a non-epistemic response to an epistemological problem. The paper employs the philosophical method of analysis, clarification, and criticism, combining this with reconstruction and clarity.


INTRODUCTION
This paper's concern is to run a survey of the intervention made by W.V.O. Quine in the debate concerning the possibility of knowledge that stands as the main concern of epistemology -theory of knowledge. As demonstrated in literature, the traditional epistemology program that is traceable to the ancient times through the modern period to the present-day inquiries in philosophy is to bring to the fore those principles, procedures, and criteria that constitute the content and scope of knowledge. This begins with the general basic question of the meaning of knowledge. What is knowledge? What can we possibly know? What are the sources of knowledge? What is the use of knowledge? To answer these questions, philosophers have come up with what has come to be referred to as the tripartite criteria of knowledge. These are belief, truth, and justification. In our navigation of W.V.O. Quine's alternative project, it would be recognized that the naturalist approach to epistemology has emerged as an important rival to more traditional ways of pursuing epistemological inquiries (Razzaque, 1996;Dolev, 2018). Since the 19th century, the onslaught on the domain of philosophy by the positivist scientists has been a growing conviction among scholars that the domain of philosophy shrinks as that of the special sciences expands that someday, science may engulf philosophy. Philosophical naturalists, obsessed with modern science promises, believe that this day may have already arrived. Naturalists suppose that philosophy does, or should share the methodologies and the basic concepts of natural sciences.

KNOWLEDGE AND THE PROBLEM OF JUSTIFICATION
According to the traditional view, the epistemological inquiry's main aim is to determine what knowledge consists of and what makes knowledge possible (Stroud, 2011). Typically, knowledge is viewed as a particular variety of true belief, namely justified true belief. Kim points out that among the three notions of epistemology, belief, truth, and justification, the most central for the epistemologist is that of justification (Jaegwon, 1988: pp. 381).
Although belief and truth may have an implicit epistemological dimension, belief is a psychological notion and truth a sematic-metaphysical one. Therefore, epistemology has it as its specific task to provide an analysis of the notion of justification and identify the criteria that beliefs must meet to qualify as justified beliefs. Since the concept of justification is fundamentally normative, epistemology is at heart a normative discipline. Practically speaking, the tenet of traditional epistemology is a normative venture. And so traditional epistemology concerned with an analysis of knowledge should help us improve our attaining knowledge. Again, Post-Fregean approaches to epistemological investigation see traditional epistemology as an a priori form of inquiry based on logical or conceptual analysis (Magada-Ward, 2010). Apriority is thus a feature of traditional epistemology. Underlying these claims proposed to be the character of traditional epistemology is a shared conception of the structure of justification.

METHOD
For purpose of emphasis, it shall be restated here that the entire problem attempted to be resolved in traditional epistemology begins with the problem of defining the meaning of knowledge (Butakov, 2018). The notion of knowledge has been differently examined in the literature. In sum, there is referred to as the tripartite definition of knowledge, that is, knowledge understood as justified true belief (JTB). By this understanding, the idea of knowledge is characterized by the notions of belief, truth, and justification. These notions shall be briefly examined here.

The Notion of Belief
Understandably, every knowledge claim is a form of belief expressed in a statement or proposition. In other words, every knowledge is a belief, but the reverse is not the case, that is every belief is not a piece of knowledge. If this is so, we, therefore, need to analyze the idea of belief. A belief is an opinion, a point of view, an assertion about the world or aspects of the world; it is a statement of a fact in the world. Moreover, this is what is to be known or denied to be known. As humans, therefore, we carry around a multitude of beliefs in our minds daily. For instance, we believe we are humans, male or female, we believe we belong to a certain race, we believe we are treated fairly or unfairly, we believe we are just or unjust. As I write this work, I believe I am sitting in my room, I believe today is Saturday, I believe my children are at home, to mention but a few. These are the essential content of knowledge. What it means, therefore, is that every knowledge I claim to have is my belief.
Therefore, it will be odd to say that I know that, "today is Saturday" but, I do not believe. Whereas, I could have said that, "I believe that Jones was fair but, I do not know," it would be odd to say that, "I know that Jones was fair, but I do not belief". Thus understood, to know include to believe. It is for this reason that it is established that every knowledge claim is a subset of belief.

The Notion of Truth
Although every knowledge claim is a subset of belief, and not all beliefs can be taken as knowledge, there must be some distinguishing between what are mere beliefs in our minds and yet not knowledge. In other words, how do we separate beliefs from knowledge? Put differently, among the myriads of beliefs we carry on our minds daily, how do we identify knowledge; for we are more secure relating with our beliefs than with our knowledge, as beliefs could be deceptive and misleading, knowledge does not. In this understanding, the notion of truth is introduced as a criterion for distinguishing between knowledge and belief. And so, for a belief to qualify as a candidate for knowledge, it must be true. Therefore, the truth condition in relation to knowledge is meant to strengthen the character of the beliefs that we hold; for, once a belief that we hold is true, it is very likely to qualify for knowledge. By this, therefore, if I know that, "the president of Nigeria has returned from his vacation", I hold a belief, and if this belief I hold corresponds to the fact, that is, the president has returned from vacation, then my belief stands a good candidate for knowledge.

The Notion of Justification
From the foregoing, it is understood that every knowledge claim is a belief, a true belief. Yet, this may not conclusively stand as knowledge. This is so because I could hold a belief, which turns out to be true, yet I have just made a good guess. Guesses are not knowledge. For then to be knowledge, there must not only be beliefs, but they must also be true, and they must be reasons for holding the belief to be true, and this is the justification condition. In this respect, if Mr. Jones holds the belief that the assembly session is holding and it is found out that the assembly session is holding, for us to take it that Mr.
Jones knows that the assembly is holding, there must be the additional condition of justifying how he came to hold the belief. What has been established so far is that knowledge is a belief that is true and justified. This is what is referred to as the tripartite understanding of knowledge. Put schematically, S knows that P (where P is a proposition and S is a subject) if and only if, • P is true, • S believes that P, and • S is justified in believing that, P. This traditional definition of knowledge known to have originated from Plato's ancient epistemology through the modern understanding of knowledge has been thoroughly criticized and objected to by philosophers, including its outright rejection by Edmund Gettier.
In his famous analysis, Edmund Gettier argued that it was very possible to hold a false belief, and yet justified and yet is taken as knowledge (Porter & Pitts 2016). What this means is that one can be justified in believing a false proposition. In response to the Gettier challenge, several pieces of literature have occurred in epistemology. Some have attempted to resolve the problem by adding further conditions or criteria. However, it is argued that even if the Gettier challenge is resolved, we would still be faced with the challenge of infinite regress about the justification of our beliefs. This is so because every true belief needs justification, and any belief proffered as the justificatory condition would still need justification. It would be difficult to have a selfjustifying belief. This is what brought to the fore of inquiry the project of epistemic foundationalism and coherentism as theories of justification.

FOUNDATIONALIST AND COHERENTIST THEORIES OF
JUSTIFICATION What are the criteria or conditions of justification? A number of theories, among which foundationalism and coherentism have been advanced by philosophers to tackle this question. Epistemic foundationalism is the claim that beliefs are said to be known or justifiably believed only because some other beliefs are known or justifiably believed. Simply put, our justified beliefs are structured like a building: they are divided into a foundation and a superstructure, the latter resting upon the former. Foundational beliefs are basic -beliefs that are non-inferentially justified, they are self-justifying (Broadbent, 2016: pp. 125). Foundationalist attempts to end the infinite series and regress of providing continuous and unending justification for every belief (Akwaji & Nchua, 2018).
The most notable foundationalist is Rene Descartes who takes as the foundation the purportedly indubitable knowledge of his own existence and the content of his ideas (Rauser, 2010). Every other justified belief must be grounded ultimately in this knowledge. This was arrived upon through his methodic doubt -a disposition to withholding assent regarding the truth or falsehood of one's beliefs until they have been demonstrated or rationally proven to be true or false. Consequently, foundationalists are faced with the challenge of how our basic beliefs are justified? Again, how do basic beliefs justify non-basic beliefs? Also, what is it that makes a justified belief basic in the first place? However, one approach accounts that what makes a justified belief basic is that it doesn't receive its justification from any other beliefs.
Adding that a subject's basic beliefs are made up of introspective beliefs about the subject's own mental states, of which perceptual experiences make up one subset. Experiential foundationalism on the other hand insists that beliefs about external objects can be basic as well. Therefore, it combines two crucial ideas: when a justified belief is basic, its justification is not owed to any other belief; and what in fact justifies basic beliefs are experiences. Another consideration is epistemic coherentism. Coherentists believe that beliefs are justified by other beliefs, but not in the acyclic way that the foundationalist hold (Broadbent, 2016, pp. 126). A belief derives it justification according to coherentism not by being based on one or more other beliefs, but by virtue of its membership in a set of beliefs that all fit together in the right way (Olsson, 2018). It is an attempt to justify belief as a holistic relationship among beliefs. One objection to coherentism about justification is that one might have a coherent set of beliefs, yet those beliefs might be false in part or whole. And so, showing that a given belief coheres with others does not amount to giving reasons to accept it as true, and thus does not amount to justifying it (Broadbent, 2016, pp. 125). Hence, coherentist needs to specify what constitutes coherence, something more than logical consistency since two unrelated beliefs may be consistent. Now, while foundationalist gives credence to a singular base for justified belief, coherentist appeals to mutual support among many beliefs.
From the foregoing, neither foundationalism nor coherentism provides an exhaustive or conclusive ground for justification of beliefs. To that extent, knowledge remains justifiable only conditionally. This is because the foundationalist theory of justification cannot provide those needed basic beliefs that are foundational, infallible, and incorrigible needed to stop the infinite regress. Moreover, even if one can provide such basic belief, how are we to judge belief that should be admitted into the structure of knowledge? On the other hand, coherentism presents a relativist mode of justification such that a belief is justified if it is coherent with other beliefs in a system of beliefs, such that it enhances the strength of the system. However, it does not appear essentially true or admissible that once a belief coheres with other beliefs in a body of beliefs that such a belief is justified. What this means is that justification is contextual. And so, again, we find ourselves wanting in justification. In all, therefore, the traditional project of epistemology runs suspect as human knowledge is such that it is deficit incertitude and justification. The best that seems available is what could be referred to as fallibilistic knowledge, which is knowledge taken to be so and yet capable of being incorrect. And this type of knowledge cannot be said to be described as episteme which is through certain indubitable knowledge. This problematic created the background for W.V.O. Quine's contention that traditional epistemology cannot deal with the traditional problem of knowledge. For him, this is so because, traditional epistemology concerns itself with the very wrong question -the question of justifying the beliefs that we hold in any conclusive sense. The question is wrong because our concern should not be about the justification of our knowledge claims or how are we to justifying our knowledge claims, rather the question should be how do we come to hold the belief that we hold, and this is a description or narrative analysis. This takes us to elucidate W.V.O. Quine's project of naturalizing epistemology.

QUINE'S PROJECT OF NATURALIZING EPISTEMOLOGY
Epistemology naturalized is rooted in certain claims held by W.V.O. Quine. Therefore, it would be charitable to present those foundations or background to aid our understanding of his view. Naturalistic epistemology indeed emerges as against the background that traditional epistemology is a normative a priori theorizing combine with the shortcomings of foundationalism. It seems that there should be a close connection between philosophical investigations of epistemological concepts (such as knowledge, justification, and rationality) with that of science. However, naturalistic epistemologists in their project differ in which science is relevant to epistemology. Again, they differ in the extent to which we employ the empirical method.
Quine's naturalized epistemology also known as replacement epistemology, takes at its starting point the fact that the criteria for justified belief must be stated without the use of epistemic terms (evaluative or normative ones), but must be formulated since descriptive or naturalistic terms alone (Jaegwon, 1988: pp. 193). He maintained that traditional epistemology should be abandoned and replaced with the methodologies of the natural sciences. Also, he shared common ground with Carnap and members of the Circle. Like them, he was and remained an empiricist, holding that all knowledge is derived from experience. Unlike them, he came to make an 'analytic tool' of the concept of experience is neither phenomenalist nor Carnapian physicalist terms, but rather in terms of stimulations of sensereceptors (Hacker, 1996: pp. 193). To that extent, he showed that the scientific study of knowledge differs from the philosophic study. While the former focuses on how humans acquire knowledge, the latter focuses on the speculative analysis of knowledge. From the above, his understanding of naturalism is that reality is to be identified and described and this is within science and not philosophy (Quine, 1981: pp. 21). On his part, science (psychology, economics, sociology, and history) is not a substitute for common sense but an extension of it -since it is a more careful attempt to improve our ordinary knowledge of the world (Quine, 1995: pp. 49).
Quine begins with the concern of epistemology which is the foundation of science. It also studies the foundation of mathematics, noting that in recent times its effort in reduction is better describable as a reduction to logic and set theory (Quine, 1994). Its earlier achievement thought to be successful in reducing mathematics altogether to logic was exposed in recent times as lacking firmness since logic in a way is privileged to set theory (Edor, 2005;Edor, 2017). Furthermore, he attempts to show that studies in the foundation of mathematics divide equally into two sorts, conceptual reduction, and doctrinal reduction. While the former is the theory of concepts or meaning, the latter is the theory of doctrine or truth (Quine, 1994: pp. 16). This division was chiefly to identify the inadequacies in philosophers' epistemological programs before him; also, the division has a grounding in his epistemology of natural knowledge. The conceptual reduction is understood with clarifying concepts by defining them, some in terms of others. Here, obscurer concepts are defined in terms of the clearer ones to maximize clarity and generate all the concepts from clear and distinct ideas (Quine, 1994: pp. 15). From this, he argues that if we claim to define all the concepts by use of some favored subset of them, we are showing that we can translate all theorems into these favored terms or the subsets. And so, it would be taken that the truth couched in them will be obviously true since the truth of mathematics is potentially obvious in the truth of logic. Quine argues here that classic epistemologists are saying the basic beliefs (favored epistemic status) be transferred, essentially to derive beliefs, a necessary condition if our derivational process is to yield knowledge from knowledge (Jaegwon, 1988: pp. 385). However, this project failed because it is obvious that mathematics reduces only to set theory and not to logic properly. Such reduction is said to enhance clarity based on interrelation not because the end terms of the analysis were clearer than others. Hence attractive as the foundation of reduction in mathematics is to philosophy, it does not grant the epistemologist how mathematical certainty is possible. This position from the classical period culminated in Rudolf Carnaps Aufbau which was to be avoided for Quine's Holism theory. The second theory -the doctrine of truth was directed at Hume's empiricism showing that "theory cannot be logically deduced from observation" (Jaegwon, 1988: pp. 186). Quine understood the doctrinal reduction to mean truths about the physical world are appropriately obtained from the truth about the sensory experience (Jaegwon, 1988: pp. 185).
In other words, they are concerned with establishing laws by proving them, some since others; less obvious laws are proved from the more obvious ones to maximize certainty (Quine 1994, pp. 15). Quine argues that David Hume was caught up in this, saying that Hume gave up the justification, having identified bodies with impression, he failed in interpreting or seeing some singular statements about bodies as indubitable truths about impressions, directly known. Again, singular statements about the future gained no increment of certainty by being about impressions (Quine, 1994: pp. 17). Hume's impression as Quine thought was harsh and a better option was contextual definition whereby sentences given meaning as wholes are undeniably meaningful regardless of whether any translations were offered for those terms in isolation (Quine, 1994: pp. 18). Adding to this, Quine applauded Bentham in his theory of fiction -paraphrasis -where he recognized that to explain a term, we do not need to specify an object for it to refer to, nor even specify a synonymous word or phrase; we need only show, by whatever means, how to translate all the whole sentences in which the term is to be used. With this combined with the division here presented as analyzed, Quine goes further to show that this also underlies the epistemology of natural knowledge saying: Just as mathematics is to be reduced to logic, logic, and set theory, natural knowledge is to be based somehow on sense experience. This means explaining the  (Quine 1994, pp. 16).
This position or bifurcation led to further explanation believed to stimulate sensory receptors, considered the central concern of epistemology naturalized. To this extent, we are to note that Quine is not asking us to give up our search for validation concerning (doctrinal and conceptual reduction), rather he thought that since the project as analyzed above failed to be executed it would be better to take up another specific project empirical psychology. In this way, the framework of 'justification-centered epistemology' would take on a purely descriptive causal-nomological science of human cognition. That is, epistemology duty is to see how the construction of theory from observation proceeds -how observation impinges cognitive agents' knowing process. Thus, philosophers are chiefly occupied with the business to see how science is developed and learned (Jaegwon, 1988: pp. 338-339). This argument clearly shows that traditional epistemology is not a factual inquiry. What is then factual is empirical psychology, in this field the sense receptors are stimulated; in this, lies evidence with which we can ultimately arrive at a holistic picture of the world. Consequently, Quine reminds us here of Ludwig Wittgenstein who theorizes earlier that "don't think, look!" This entails looking at human practice. And justification is located within this practice which is rightly located in psychology -by this, he meant behaviorism. His motivation for behaviorist psychology was on the ground that the only evidence one has for what a scientist does in arriving at his picture of the world is the scientist's practice. How do we accept this? Quine thinks that we are to look without preconceptions or precondition at the behavior of scientists, in doing this, we realize that they do not engage in reconstruction or fantasy or make-believe statements as philosophers do, they rely on the stimulation of their sensory receptors (Stroll, 2000: pp. 92). Knowledge is therefore an outcome of a natural process whereby sensory stimulation leads to theories about the world. Thus, to understand the connection between the stimulation and the theories and understand how far beyond the stimulation our theories go -we study the process scientifically (Wren, 2016). Quine insists that our epistemological theories must fit appropriately with the rest of our scientific worldview. Its concern now is to analyze how 'meagre input' becomes a 'torrential output' to settle the relationship between theory and evidence finally.
From the foregoing, it is evident that Quine privileges the use of empirical psychology, what is conspicuous, a careful reflection combines with a posteriori bases and description to be the proper method to arrive at an accurate understanding of the true epistemological principles and facts. Obviously, nonnormative concepts such as theories, observation, and science figure repeatedly in his work. Fundamental concepts such as knowledge, justification among others having normative character, investigated on a priori grounds are now to be pursued in a descriptive term.

CONCLUSION
It is to be reiterated here that W.V.O. Quine's naturalizing epistemology project was a sincere, attempt to rescue epistemology from his background of positivism. And so, he began with the position that traditional epistemology has concerned itself with a 'wrong question,' which is the question of providing ground of justification for the knowledge that we hold. In his opinion, the appropriate demand is not that of providing grounds of justification but should be that of explaining how we come to hold the beliefs that we hold. By this understanding, the beliefs that we hold are received from our environment (social, political, spiritual, etc.) by our sensory receptors, which are then interpreted by the brain and the central nervous system. This is what he referred to as "meagre input and torrential output." The external world's facts come to our senses as meagre input and the beliefs that we hold are torrential output. Therefore, the programmed should not be that of justifying our knowledge claims but, explaining how we come to hold the belief that we hold. Such that epistemology should not be about justification but, should be about explanation; it should not be that of prescription but, that of description. And this is the crux of the critique of naturalizing epistemology. If epistemology is stripped of its normative character replaced by a descriptive posture or framework, its normativity becomes suspect. In short, if epistemology is removed from philosophy and taken to a book in psychology then the essential question will be what is the normative nature of naturalizing epistemology. This is the question raised by a few philosophers including Jeagwon Kim.